Function of a single angle! Please Help!

Question

Express this as a function of a single angle:

tan 55°-tan 17°/1+tan 55°tan 17°

Answer 1

Since the Sum/Difference Identity for Tangent states...

Comparing this to your problem, you would use the difference version and get:

Answer 2

This is an example of the formula for the tangent of a difference of two angles. Locate a list of these formulas in your book and know how to use them

(tan u - tan v) / (1 + tan u tan v) = tan Iu - v)

The given numbers reduce to tan (55° - 17°) or tan 38°